Object.assign for old versions

asvny · web-flow · commit 7ae720a2d7fb · 2017-02-27T16:21:12.000+05:30
diff --git a/lib/resolve-value.js b/lib/resolve-value.js
@@ -5,6 +5,31 @@ var gatherVariableDependencies = require('./gather-variable-dependencies');
 var findNodeAncestorWithSelector = require('./find-node-ancestor-with-selector');
 var cloneSpliceParentOntoNodeWhen = require('./clone-splice-parent-onto-node-when');
 
+if (typeof Object.assign != 'function') {
+  Object.assign = function(target, varArgs) { // .length of function is 2
+    'use strict';
+    if (target == null) { // TypeError if undefined or null
+      throw new TypeError('Cannot convert undefined or null to object');
+    }
+
+    var to = Object(target);
+
+    for (var index = 1; index < arguments.length; index++) {
+      var nextSource = arguments[index];
+
+      if (nextSource != null) { // Skip over if undefined or null
+        for (var nextKey in nextSource) {
+          // Avoid bugs when hasOwnProperty is shadowed
+          if (Object.prototype.hasOwnProperty.call(nextSource, nextKey)) {
+            to[nextKey] = nextSource[nextKey];
+          }
+        }
+      }
+    }
+    return to;
+  };
+}
+
 // var() = var( <custom-property-name> [, <any-value> ]? )
 // matches `name[, fallback]`, captures "name" and "fallback"
 // See: http://dev.w3.org/csswg/css-variables/#funcdef-var
